The present invention relates to a system for removing the oil from the surface of water from the bilge area and elsewhere of recreational boats and small commercial vessels. The system will allow the bilge pump to discharge water overboard ranging from a minimum of oil to water free of oil. This in turn will prevent pollution of the environment.
The system can also be applied to absorbing oil from the surface of the water being processed in small industrial plant oil wastes, oil slicks or oil spills that may result from maritime oil spill incidents.
The Federal Water Pollution Control Act (FWPCA) prohibits the discharge of oil or hazardous substances into the water of the United States. This prohibition is stated with respect to these terms: "discharge" includes spilling, leaking, pumping, pouring or dumping; and "oil" means any kind of oil in any form, including fuel oil, gasoline, lubricating oil and oil mixed with water in a vessel's bilge. The standard further states that oil has been discharged in a harmful quantity if it causes a rainbow, a film, a sheen or discoloration upon the surface of the water.
At the present time, vessels with inboard engines commonly have bilges that collect water, fuel oil, gasoline, and lubricating oil. For safety purposes most vessels have an automatic bilge pump to pump the excessive mixed oily water overboard to avoid flooding. Further, prior to starting of the engine and during the operation of an engine, the bilge pump is periodically operated to further remove the combination of the bilge oil and water. Commonly, this will result in the discharge of a harmful quantity of oil as determined by the above standards.
One way that has been suggested to meet the above standards is to provide a holding tank within the boat, into which the oily bilge water is pumped during the operation of the bilge pump, so that the oily bilge water can further be pumped to an onshore system.
Large oil water separators have been provided for large ships, but the size and cost of these systems generally prohibit their use on recreational boats and small commercial vessels of the type described above. Further, such systems are mainly concerned with recovering bulk oil and not removing the small quantities of oil. These systems are incapable of meeting the above standards.
Smaller sized oil water separators for removing small quantities of oil from the water are becoming available to recreational boat and small commercial vessel operators, for example as shown in U.S. Pat. No. 3,913,513. While these bilge pump oil filters meet the standards set forth above and usually have an operating life cycle of six to twelve months, they have the following limitations such as: a. space available in the hull for the canister, b. whether the boat is operated on limited basis or on daily operations such as charter fishing boats and c. the operating condition of the engine. While these bilge pump oil filters can satisfy the regulation for discharging oily bilge water, free of oil, their length of operation is subjected to many variables.
Gasoline and diesel oil are also discharged into the environment when the boats take on fuel and there is leakage in the vicinity of the filling nozzle and fuel tank filler opening. This leakage falls directly into the water or indirectly as run-off from the deck.